1. Field of the Invention
The present invention relates to simulations of tennis games which can be played immediately, without the necessity of finding an opponent, as a practice device to develop the physical skills of the player.
2. Description of the Prior Art
Automatic ball hurling machines have been used in various sports for more than a generation. Baseball throwing machines have been designed which simulate various types of spin, thereby simulating curve balls and other pitches. Tennis balls hurling machines must be reloaded by hand, so that for efficient operation, vast quantities of tennis balls are required. Since tennis balls lose their liveliness a short time after removal from the can, it has been economically unfeasible to provide automatic tennis ball machines for the general public. In addition, the requirement for reloading means that the average machine is only being used about 50% of the time, with the other 50% of the time being used to reload.
While prior art baseball machines have been devised simulating baseball pitches, no prior art tennis machine has been capable of simulating the vast variety of possible tennis shots. Baseball machines have generally been purchased by teams having considerable financial backing. Since tennis is a public sport participated in by people who are making considerably less than the average baseball salary, a tennis ball machine must be relatively inexpensive to manufacture.
Land prices in urban areas seem to continually increase to previously unthought of levels. A player practicing against a machine does not need a full court. All that is needed is a simulation of conditions which exist when he plays against an opponent on a full court.
Because of the nature of the cover of the tennis ball and the fact that a tennis ball is struck by a racket having strings therein, and because frequently a tennis ball will hit the ground before it is returned, a wide variety of spins must be simulated in order to simulate tennis. The necessary number of spins vastly exceeds the number required to be put on a baseball by an automatic baseball throwing machine, because the tennis racket can do everything with a tennis ball that a baseball pitcher can do, and can do considerably more besides.